Acke Guillaume, Van Hende Daria, De Vriendt Xeno, Bultinck Patrick
Department of Chemistry - Ghent Quantum Chemistry Group, Ghent University, Krijgslaan 281 (S3), Ghent B-9000, Belgium.
J Chem Theory Comput. 2023 Aug 22;19(16):5418-5426. doi: 10.1021/acs.jctc.3c00080. Epub 2023 Aug 2.
As a matrix extension of the Fukui function, a reactivity descriptor grounded within Conceptual Density Functional Theory, the Fukui matrix extends Frontier Molecular Orbital Theory to correlated regimes with its eigendecomposition in Fukui occupations and Fukui naturals. Despite successful applications, the questions remain as to whether replacing a quantity derived from a purely density-based framework by its matrix extension is theoretically well-founded and what chemical information is contained in the corresponding eigendecomposition. In this study, we show that the matrix extension of the Fukui function is only well-defined if one also generalizes the external potential to become nonlocal, leading to the introduction of Conceptual First-Order Reduced Density Matrix Functional Theory. By interpreting the Anderson impurity model from an interacting open subsystem perspective, we show how Fukui occupations and Fukui naturals reflect the influence of an increasing (static) correlation and which characteristic patterns we should expect within a molecular context. This study represents a step in generalizing Conceptual Density Functional Theory beyond its density-based perspective.
作为福井函数的矩阵扩展，福井矩阵是基于概念密度泛函理论的一种反应性描述符，它通过福井占据数和福井自然轨道的本征分解将前沿分子轨道理论扩展到相关体系。尽管有成功的应用，但用其矩阵扩展来取代从纯基于密度的框架导出的量在理论上是否合理，以及相应本征分解中包含哪些化学信息，这些问题仍然存在。在本研究中，我们表明，只有当同时将外部势推广为非局部时，福井函数的矩阵扩展才是明确定义的，这导致了概念性一阶约化密度矩阵泛函理论的引入。通过从相互作用的开放子系统角度解释安德森杂质模型，我们展示了福井占据数和福井自然轨道如何反映增强的（静态）相关性的影响，以及在分子背景下我们应该预期哪些特征模式。这项研究代表了将概念密度泛函理论从基于密度的视角进行推广的一个步骤。
